THE INFLUENCE OF DIFFERENT SPECIES OF YEAST ON MYCOTOXINS CONCENTRATIONS IN WHEAT
The aim of this study was to evaluate the effect of Saccharomyes cerevisiae, Geotrichum fermentans, Rhodotorula rubra and Kluyveromyces marxianus yeast cell suspensions and Saccharomyces cerevisiae cell wall’s polysaccharides and fermentation time on mycotoxins concentrations in feed wheat. The 2018 harvest three feed wheat samples were taken from grain processing companies and the research was carried out at the Lithuanian University of Health Sciences, Veterinary Academy, Mycotoxicology Laboratory. The thin – layer chromatography technique (TLC) was used to determine mycotoxins concentrations in the samples. The wheat samples were inoculated with Saccharomyces cerevisiae, Geotrichum fermentans Rhodotorula rubra and Kluyveromyces marxianus yeast 104 cells` ml-1 suspensions and Saccharomyces cerevisiae cell wall`s polysaccharides, duration of the wheat fermentation with the yeast was – 30 min. and 60 min. It was found that all species the yeast suspensions – reducing effect of mycotoxins concentrations correlated with longer duration of fermentation. Saccharomyces cerevisiae yeast suspension after 60 min. reduced AFB1 and DON by 100% (p<0.05) and ZEA up to 80.1 ± 0.50% (p<0.05). Saccharomyces cerevisiae yeast cell wall`s polysaccharides decreased the concentrations of AFB1 (p>0.05), ZEA (p<0.05), DON (p<0.05) during the experiment better than Saccharomyces cerevisiae 104 cells` ml-1 suspension and after 60 min. exposure polysaccharides absorbed all wheat mycotoxins by 100% (p<0.05). The AFB1 were best absorbed by Kluyveromyces marxianus yeast after 60 min. of fermentation by 100% (p<0.05). The DON concentration was below the detection limit after 60 min. of fermentation with Geotrichum fermentans and Rhodotorula rubra yeast.